North Korean test potentially twice as powerful as last one in January

According to CNN — North Korea said it has hit the button on its fifth and potentially most powerful nuclear test Friday morning, claiming to have successfully detonated a nuclear warhead that could be mounted on ballistic rockets.

State media said the test would enable North Korea to produce "a variety of smaller, lighter and diversified nuclear warheads of higher strike power."

"It's hard for us to verify their claim. My deep fear is that they will launch a live nuclear weapon on one of their missiles, but that would be extremely dangerous as that could trigger a war," said Melissa Hanham, a senior research associate at the James Martin Center for Nonproliferation Studies.

World leaders condemned the test , saying it was a clear violation of UN Security Council resolutions, and the Security Council plans to hold an emergency meeting on the issue Friday.

US "does not, and never will, accept North Korea as a nuclear state," Obama says